The July 2013 issue of Astronomy Now is on sale at newsagents or available direct by from our online store.

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Focus: An illustrated timeline of twentieth century astronomy

The twentieth century was a watershed in astronomy. So much was learnt, so much was improved that it is impossible to compare astronomy in the Victorian age to the realms that astronomical research explores today.

The Great Debate and Hubble's discovery of 'island universes' and the expansion of the cosmos.

Jocelyn Bell found fame with her discovery of pulsars as a PhD student and the first human explorers step foot on the Moon.

Features

A superb new image from the European Southern Observatory of the famous Ring Nebula is teaching us about the inner workings of planetary nebulae.

Mark Armstrong went to New York's North-East Astronomy Forum to rub shoulders with the latest telescopes and keen amateurs alike.

Our editor, Keith Cooper, speaks to Major Timothy Peake, the UK's first official astronaut, who is flying to the International Space Station in 2015.

It is 50 years since the discovery of quasars and Keith Cooper sets about investigating what we have learned about them in that time, by speaking to the scientist that discovered them.

Neil English picks a selection of hot deep sky targets for observing on the warm nights of summer.

Regulars

Making news this month: Kepler planet discovery is small 'Beer' • Revolutionary planet-finder has wobbly aim • Mars' water was drinkable • The Moon was born wet • The Sun's neighbourhood gets a lot bigger

In The Night Sky section this month: All the planets are visible to see - just - with Uranus, Venus and Saturn being the standouts. Plus, tour a multitude of planetary nebulae.

This summer take your time to bask in the glory of possibly the best planetary nebula in the entire sky, the stunning Dumbbell Nebula, M27, in Vulpecula.

Eyepiece filters have the ability to transform the view through the telescopic eyepiece, explains Neil English.

Steve Ringwood takes a liking to Sky-Watcher's latest small telescope as part of its heritage legacy, the 114P Virtuoso.

Download a free PDF version of the January 2011 issue of Astronomy Now. (20 MB file)

The PlanetsFrom tiny Mercury to distant Neptune and Pluto, The Planets profiles each of the Solar System's members in depth, featuring the latest imagery from space missions. The tallest mountains, the deepest canyons, the strongest winds, raging atmospheric storms, terrain studded with craters and vast worlds of ice are just some of the sights you'll see on this 100-page tour of the planets. GET YOUR COPY

Hubble RebornHubble Reborn takes the reader on a journey through the Universe with spectacular full-colour pictures of galaxies, nebulae, planets and stars as seen through Hubble's eyes, along the way telling the dramatic story of the space telescope, including interviews with key scientists and astronauts. GET YOUR COPY

3D UniverseWitness the most awesome sights of the Universe as they were meant to be seen in this 100-page extravaganza of planets, galaxies and star-scapes, all in 3D! GET YOUR COPY